The present invention, in some embodiments thereof, relates to an ingestible phototherapy device which may be used for treating diseases of the gastrointestinal tract, and in particular, for treating inflammatory bowel disease (IBD), using phototherapy.
Light therapy, conventionally referred to as “phototherapy”, comprises exposing living tissue to light to treat a disease of the organism or tissue. The exposure is typically provided in accordance with a particular protocol tailored to the disease that defines spectrum and intensity of light used to illuminate the tissue and total energy deposited in the tissue by the light. The light may be generated using any of various suitable light sources, such as lasers, light emitting diodes (LEDs) and fluorescent lamps.
Phototherapy is generally applied to relatively easily accessible tissue regions, such as external regions of the skin and the mucosa lining the mouth or nose, and is used to treat acne, psoriases, eczema, vitiligo (in which damage to skin pigment cells results in white skin patches) and skin-based lymphoma, gingivitis, gum inflammations, oral ulcers, and allergic rhinitis.
Phototherapy for treatment of diseases of the gastrointestinal (GI) tract is generally not performed because of the relative difficulty in accessing GI tract tissue.
A similar-sounding but different field from phototherapy is Photodynamic Therapy (PDT). Most modern PDT applications involve three key components: a photo-sensitizer, a light source and tissue oxygen. The wavelength of the light source needs to be appropriate for exciting the photo-sensitizer to produce reactive oxygen species. The combination of these three components leads to the chemical destruction of any tissues which have either selectively taken up the photo-sensitizer or have been locally exposed to light. In understanding the mechanism of PDT it is important to distinguish it from other light-based and laser therapies such as laser wound healing and rejuvenation which do not require a photo-sensitizer.
International Patent Application Publication No. WO2008/012701 is entitled “Capsule camera with variable illumination of the surrounding tissue”, and discloses an ingestible capsule and method for in vivo imaging and/or treatment of one or more diseased areas of interest within the gastrointestinal tract of an animal or human being. The capsule comprises an image sensor; a lens system for focusing images onto the image sensor; at least one light source for illumination of the tissue area of interest, the at least one light source optionally being capable of providing optical therapeutic treatment to the diseased areas; a variable lens system located in front of the at least one light source, wherein the variable lens system comprises beam steering means and focusing means for directing and focusing the light beams from the at least one light source onto the diseased tissue areas, a control unit in communication with the image sensor, the at least one light source, and variable lens system, a power source for powering the image sensor, the at least one light source and the control unit; and a non-digestible, transparent outer protective shell configured to pass through the gastrointestinal tract, housing within the image sensor, the lens system, the at least one light source, the variable lens system, the control unit and the power source.
An article entitled “Autonomous Device for Photostimulation of the Gastrointestinal Tract Immunity” by Sergey A. Naumov, Vladimir N. Dyrin, Sergey M. Vovk, Evgeny Y. Petrov, Vladimir V. Udut and Elena V. Borodulina, published in Proc. SPIE 3907, 433 (2000); doi:10.1117/12.386284, describes a very small optoelectronic device emitting light in the red and green band has been developed as a small capsule consisting of two semispheres connected with light-transmitted coupling. The device—a phototablet permits to irradiate all parts of the gastro-intestinal tract (GIT) including the immunocompetent formations of the small intestine —Peyer's patches responsible for production of secretory immunoglobulins A (IgA). The main mechanisms of realizing endogenic phototherapy using a phototablet begin functioning when irradiating both the walls of the GIT organs and its contents. The results of clinical trials of the phototablet testify to a favorable effect of endogenic therapy on the human organism in asthenic syndrome, some types of deficiency in the immunity function, in dysbioses, the syndrome of large intestine irritation, duodenostasis, etc. After endogenic phototherapy the patients had an increased level of lysozyme, leukocytes, a number of lactobacteria. There were no side effects when using a phototablet. Indications and contraindications for endogenic phototherapy were represented. Thus, the method of endogenic phototherapy allows us to have an effective and direct influence on the immunocompetent cells of GIT organs without medicamental agents and antigens that makes it possible to use the phototablet in medicine on a large scale.
U.S. Patent Application Publication No. 2009/0177033 of Hendriks et al., describes an application which relates to an ingestible capsule and method for in vivo imaging and/or treatment of one or more diseased areas of interest within the gastrointestinal tract of an animal or human being. The capsule comprises an image sensor; a lens system for focusing images onto the image sensor; at least one light source for illumination of the tissue area of interest, the at least one light source optionally being capable of providing optical therapeutic treatment to the diseased areas; a variable lens system located in front of the at least one light source, wherein the variable lens system comprises beam steering means and focusing means for directing and focusing the light beams from the at least one light source onto the diseased tissue areas, a control unit in communication with the image sensor, the at least one light source, and variable lens system, a power source for powering the image sensor, the at least one light source and the control unit; and a non-digestible, transparent outer protective shell configured to pass through the gastrointestinal tract, housing within the image sensor, the lens system, the at least one light source, the variable lens system, the control unit and the power source.
Additional background art includes:
an article titled: “Compartmental Transit and Dispersion Model Analysis of Small Intestine Transit Flow in Humans”, by Lawrence X. Yu, John R. Crison and Gordon L. Amidon, published in International Journal of Pharmaceutics, Vol, 40; 1999;
an article titled: “Relationship of Gastric Emptying and Volume Changes After Solid Meal in Humans”, by Duane D. Burton, H. Jae Kim, Michael Camilleri, Debra A. Stephens, Brian P. Mullan, Michael K. O'Connor, and Nicholas J. Talley, published in Am J Physiol Gastrointest Liver Physiol 289, 2005;
an article by Wirtz et al., published in Nature Protocols, Vol. 2, pp. 541-546, 2007;
PCT published patent application WO 2009/102445 of Bandy et al;
US published patent application 2008/0106596 of Iddan et al;
US published patent application 2004/0249245 of Trion;
US published patent application 2004/0106849 of Cho et al;
US published patent application 2003/0214579 of Iddan; and
U.S. Pat. No. 5,464,436 to Smith.